/**
 * Copyright (c) 2010 by Kevin Bierhoff.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *    1. Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *    2. Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *    3. Neither the names of the authors nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ''AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.googlecode.syper.javasyp.formulae;

/**
 * @author kevin
 * @since Sep 6, 2010
 */
public class IfThenElse implements Formula {

	private final Formula condition;
	private final Formula thenFormula;
	private final Formula elseFormula;

	/**
	 * @param condition
	 * @param thenFormula
	 * @param elseFormula
	 */
	public IfThenElse(Formula condition, Formula thenFormula,
			Formula elseFormula) {
		super();
		this.condition = condition;
		this.thenFormula = thenFormula;
		this.elseFormula = elseFormula;
		if (! condition.isBoolean())
			throw new IllegalArgumentException("Condition not boolean: " + toString());
		if (thenFormula.isBoolean()) {
			if (! elseFormula.isBoolean())
				throw new IllegalArgumentException("Branch types don't match: " + toString());
		} else if (elseFormula.isBoolean()) {
			throw new IllegalArgumentException("Branch types don't match: "
					+ toString());
		}
	}

	public Formula getCondition() {
		return condition;
	}

	public Formula getThenFormula() {
		return thenFormula;
	}

	public Formula getElseFormula() {
		return elseFormula;
	}

	@Override
	public <T> T dispatch(FormulaVisitor<T> visitor) {
		return visitor.visit(this);
	}

	@Override
	public boolean isBoolean() {
		return thenFormula.isBoolean() && elseFormula.isBoolean();
	}

	@Override
	public String toString() {
		return "(" + condition + " ? " + thenFormula + " : " + elseFormula + ")";
	}

}
